1. Field of the Invention
The invention is directed to a laser volume sensor used on a combine for either detecting the amount of tailings being transported by the tailings elevator, or the amount of clean grain being transported by the clean grain elevator.
2. Description of the Prior Art
Combines are large agricultural machines used to harvest a crop from a field. After the crop is harvested by a harvesting platform, the crop material is transported by a feederhouse into the interior of the combine. A threshing assembly threshes the harvested crop material breaking the grain apart from other grain and/or a husk. Next a separator assembly separates the clean grain the crop material other than grain. The crop material other than grain is returned to the field, while the grain and entrained small particles, chaff, are directed to a cleaning system. The cleaning system cleans the grain removing the chaff by blowing the chaff out the rear of the combine. The clean grain is transported by a clean grain elevator to a grain tank located on the combine. Photoelectric sensors for measuring the volume of clean grain passing through the clean grain elevator have been proposed, see German patent 2,445,046.
Sometimes clean grain, unthreshed heads of grain and other crop material pass over the sieves of the cleaning system and become tailings. These tailings are caught before being expelled from the combine. The tailings are returned to the threshing assembly by a tailings elevator. Photodiode sensors for measuring the volume of tailings passing through the tailings elevator have also been proposed, see U.S. Pat. No. 4,441,513.